This invention relates to a three-dimensional image processing apparatus and an external memory device to be used therewith. More particularly, the invention relates to a three-dimensional image processing apparatus which is adapted to display an image of a player controlled object or other objects, existing in three-dimensional space, when viewed from predetermined points of view.
The conventional so-called three-dimensional (3D) game uses player controlled or operable objects (objects controllable by an operator) configured with three-dimensional data when viewed by an apparent camera at predetermined angles and distances, thereby obtaining displayed images. In the conventional game, however, if a background image (e.g., a wall) or an object used as an opponent character (e.g., a programmed controlled object) comes between the player controlled operable object and the xe2x80x9ccameraxe2x80x9d, or if another object is moved to interrupt the line of sight between the operable object and the camera, the operable object can not be viewed in the three-dimensional world. To this end, there has been a limitation in conventional 3D games in that the other object has to be arranged by program not to exist between the operable object and the camera.
It is therefore an object of the present invention to provide an image processing apparatus which is capable of displaying an operable object at substantially all times and is hence free from limitation in arranging other objects.
The illustrative image processing apparatus displays an operable object image and another object existing in a three-dimensional space from a predetermined viewing or xe2x80x9cphotographicxe2x80x9d position. The system includes an external memory which stores operable object and other object data and a video game program. The system uses a unique player controller which inputs data that alters the position of the operable object in the three-dimensional space. Operable object position data generating hardware and software generates operable object position data so as to alter the position of the operable object in the three-dimensional space based on the data input by the controller. Three-dimensional data is created based on the data stored in the external memory and the operable object position data. Point of view position data is generated representing a photographing position in the three-dimensional space for displaying the operable object. The system detects whether or not another object exists between the xe2x80x9ccameraxe2x80x9d view position and the operable object position. If so, the system alters the photographing position data such that the other object is not existent between the photographing position and the operable object position. A three-dimensional display is created for displaying the image of the operable object photographed from a predetermined position in the three-dimensional space.
The system determines whether there is a possibility of a collision between the operable object and a polygon plane of the other object. If there is a possibility of a collision between the operable object and the other object, the camera position is changed, so that the other object does not exist between the operable object and the camera. Therefore the operable object is viewed without interference by another object.
In accordance with the present invention, even if another object is permitted to freely move, it is possible to display at substantially all times an operable object on a display screen. Consequently, if the present invention is applied to a game apparatus, the operable object can be displayed at all times on a display, even for a game that involves an operable object and a number of other objects moving around on the display screen.
The present video game methodology uses plural xe2x80x9ccameraxe2x80x9d (i.e., the displayed point of view in the three-dimensional world) modes and embodies automatic manipulation of the xe2x80x9ccameraxe2x80x9d angle in response to the user""s actuation of a plurality of distinct controller keys/buttons/switches, e.g., four xe2x80x9cCxe2x80x9d buttons in the exemplary embodiment, the detected position of the player controlled character, and the occurrence of predetermined special events during game play. By utilizing varied camera modes game play occurs with more realistic varied image expression. The invention permits the player controlled object to be displayed and manipulated such that the player has enhanced character controllability. Through the capability of displaying a scene from all directions a player is enable to discover, for example, an enemy hiding behind an object, or around a bend, etc. As explained herein, through the use of a unique controller joystick, the player also has an opportunity to control the camera angle to gain a fuller understanding of the surrounding terrain and position in the three-dimensional world screen display
The control keys allow the user at any time to move in for a close up or pull back for a wide view or pan the camera to the right and left to change the apparent camera angle. Such user initiated camera manipulation permits a player to better judge jumps or determine more precisely where an object is located in relation to the player controlled character. For example, one camera perspective control button allows the user to switch to a perspective which is adjusted to be directly behind the player controlled character. In this fashion, portions of the game where there is a very narrow platform or enclosed space which must be traversed, may be more successfully traversed. The shooting direction may be changed by operation of the unique controller""s joystick to change the direction of the character""s head to smoothly control direction shifts in which the player wants to see. By utilizing the ability to switch three-dimensional display perspectives, a player can advantageously enhance success in the game by gaining a better angle to attack a jump, navigate a narrow ledge or discover what is around a corner. Thus, a player may achieve a higher score than otherwise would be possible by judicially changing the camera angle.
In accordance with an exemplary embodiment of the present invention, the present video game system automatically changes the apparent moving direction of the camera or modifies the apparent camera angle depending upon the controlled character""s circumstance, e.g., is he inside a castle, outside a castle, inside a room, running, flying, swimming, etc. In instances where the game processor detects that, for example, a wall exists between, for example, the player controlled character and a camera point of view, a calculation is made as to the required camera movement to prevent obstruction between the eye of the camera and the operable object. The camera is then moved to a new position in accordance with the calculated moving angle. The camera perspective is automatically changed to select the best camera angle according to the character""s circumstances so the player can enjoy the visual effects being experienced in a three-dimensional world.